de-Broglie wavelength, λ=mvh=10−3(6×10143×108)[∵λ=vc] v=9.1×10−31×3×1056.63×10−34×6×1014v=1.45×106 m/s
JEE Main 2019 — Physics Modern Physics
If the deBroglie wavelength of an electron is equal to 10− times the wavelength of a photon of frequency 6×1014 Hz, then the speed of electron is equal to : (Speed of light =3×108 m/s) Planck's constant =6.63×10−34 J.s Mass of electron =9.1×10−31 kg)
Held on 11 Jan 2019 · Verified 6 Jul 2026.
1.1×106 m/s
1.7×106 m/s
1.8×106 m/s
1.45×106 m/s
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